Introduce the coresight_enable_source() helper for enabling source device, refine the comment for the imbalance between enable and disable pair functions.
Add validation to ensure the device is a source before proceeding with further operations.
Reviewed-by: James Clark james.clark@linaro.org Tested-by: James Clark james.clark@linaro.org Reviewed-by: Yeoreum Yun yeoreum.yun@arm.com Signed-off-by: Leo Yan leo.yan@arm.com --- drivers/hwtracing/coresight/coresight-core.c | 20 +++++++++++++++++--- drivers/hwtracing/coresight/coresight-etm-perf.c | 2 +- drivers/hwtracing/coresight/coresight-priv.h | 3 +++ drivers/hwtracing/coresight/coresight-sysfs.c | 2 +- 4 files changed, 22 insertions(+), 5 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c index 7186e7d948829479dfe5ea95c8cd5a03df5fc26c..4b55c54c5fbade99404ad662aa4111d4c3c2b85b 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -416,17 +416,31 @@ static void coresight_disable_helpers(struct coresight_device *csdev, }
/* - * Helper function to call source_ops(csdev)->disable and also disable the - * helpers. + * coresight_enable_source() only enables the source but does nothing for the + * associated helpers. In contrast, coresight_disable_source() calls + * source_ops(csdev)->disable() and also disables the helpers. * * There is an imbalance between coresight_enable_path() and * coresight_disable_path(). Enabling also enables the source's helpers as part * of the path, but disabling always skips the first item in the path (which is * the source), so sources and their helpers don't get disabled as part of that - * function and we need the extra step here. + * function and we need the extra step in coresight_disable_source(). */ +int coresight_enable_source(struct coresight_device *csdev, + struct perf_event *event, enum cs_mode mode, + struct coresight_path *path) +{ + if (!coresight_is_device_source(csdev)) + return -EINVAL; + + return source_ops(csdev)->enable(csdev, event, mode, path); +} + void coresight_disable_source(struct coresight_device *csdev, void *data) { + if (!coresight_is_device_source(csdev)) + return; + source_ops(csdev)->disable(csdev, data); coresight_disable_helpers(csdev, NULL); } diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c index a2c1c876099d1f5dacf039d733b78827296d9c2e..6783396635b7a62328483ad5d8837c9a59990e50 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.c +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c @@ -533,7 +533,7 @@ static void etm_event_start(struct perf_event *event, int flags) goto fail_end_stop;
/* Finally enable the tracer */ - if (source_ops(csdev)->enable(csdev, event, CS_MODE_PERF, path)) + if (coresight_enable_source(csdev, event, CS_MODE_PERF, path)) goto fail_disable_path;
/* diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h index c96d63657f9334be890cca2320abbb8cbd807802..51ff1718502d6a5bf86b16e0723d7cdfdecc1848 100644 --- a/drivers/hwtracing/coresight/coresight-priv.h +++ b/drivers/hwtracing/coresight/coresight-priv.h @@ -249,6 +249,9 @@ void coresight_add_helper(struct coresight_device *csdev, void coresight_set_percpu_sink(int cpu, struct coresight_device *csdev); struct coresight_device *coresight_get_percpu_sink(int cpu); struct coresight_device *coresight_get_percpu_source(int cpu); +int coresight_enable_source(struct coresight_device *csdev, + struct perf_event *event, enum cs_mode mode, + struct coresight_path *path); void coresight_disable_source(struct coresight_device *csdev, void *data); void coresight_pause_source(struct coresight_device *csdev); int coresight_resume_source(struct coresight_device *csdev); diff --git a/drivers/hwtracing/coresight/coresight-sysfs.c b/drivers/hwtracing/coresight/coresight-sysfs.c index 2546f3ef82f810fd04a119cecd2093b8150112b6..de1cc05433f565eb7cb91e386f79939857dadcd5 100644 --- a/drivers/hwtracing/coresight/coresight-sysfs.c +++ b/drivers/hwtracing/coresight/coresight-sysfs.c @@ -66,7 +66,7 @@ static int coresight_enable_source_sysfs(struct coresight_device *csdev, */ lockdep_assert_held(&coresight_mutex); if (coresight_get_mode(csdev) != CS_MODE_SYSFS) { - ret = source_ops(csdev)->enable(csdev, NULL, mode, path); + ret = coresight_enable_source(csdev, NULL, mode, path); if (ret) return ret; }